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<table width="100%" summary="page for darwin"><tr><td>darwin</td><td style="text-align: right;">R Documentation</td></tr></table>

<h2>
Darwin's Plant Height Differences
</h2>

<h3>Description</h3>

<p>The <code>darwin</code> data frame has 15 rows and 1 columns.
</p>
<p>Charles Darwin conducted an experiment to examine the superiority of
cross-fertilized plants over self-fertilized plants.  15 pairs of plants
were used. Each pair consisted of one cross-fertilized plant and one
self-fertilized plant which germinated at the same time and grew in the
same pot. The plants were measured at a fixed time after planting and
the difference in heights between the cross- and self-fertilized plants are
recorded in eighths of an inch.
</p>


<h3>Usage</h3>

<pre>
darwin
</pre>


<h3>Format</h3>

<p>This data frame contains the following column:
</p>

<dl>
<dt><code>y</code></dt><dd>
<p>The difference in heights for the pairs of plants (in units of 0.125 inches).
</p>
</dd></dl>


<h3>Source</h3>

<p>The data were obtained from
</p>
<p>Fisher, R.A. (1935) <em>Design of Experiments</em>. Oliver and Boyd.
</p>


<h3>References</h3>

<p>Darwin, C. (1876) 
<em>The Effects of Cross- and Self-fertilisation in the Vegetable Kingdom</em>. 
John Murray.
</p>
<p>Davison, A.C. and Hinkley, D.V. (1997) 
<em>Bootstrap Methods and Their Application</em>. Cambridge University Press.
</p>


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